Just before WW2 the Germans produced a gas that the existing British gasmask filter would not protect against. As a stopgap a second smaller filter which would stop the new gas was added above the existing filter, this was not ideal as it made breathing even more difficult.
The masks were, in theory, all modified with a new filter and the second cans disposed of but a few have survived making them extremely scarce.
The mask and main filter are both dated 1938 and in a 1940 MkVI bag, I may have a MkV bag available later. The hose has been somewhat crushed through long storage in a bag that was always too small for it.
Under no circumstances should an old gasmask be used/worn.
Photo shows actual item.
This is an item from my private condition, as such payment will need to be made by bank transfer or paypal